By performing dynamic adaptive weighting on multiple array elements in horizontal and vertical directions, an AAS (active antenna system) is enabled with a capability of performing dynamic adaptive BF (beam forming) in horizontal and vertical directions, thereby improving signal transmission quality and the like. However, in a wireless communication system such as LTE-A (Long Term Evolution Advanced), a UE needs to perform CSI (channel state information) measurement to obtain better BF performance.
In the prior art, when CSI measurement is implemented, because a set of CSI-RS (channel state indication reference signal) resources of 3GPP Rel-11 (3rd Generation Partnership Project Release 11) support a maximum of eight ports, all ports are supported by one to multiple sets of CSI-RS resources when the number of pilot ports of a transmitting array is greater than or equal to 8. In duplex mode, especially in FDD (frequency division duplex), a BS sends one to multiple sets of CSI-RS resources to a UE (user equipment), and the UE performs CSI measurement on ports of a transmitting array separately on each set of CSI-RS resources.
During the implementation of the present invention, the inventor finds that the prior art has at least the following problem:
When the number of ports of a transmitting array is greater than 8, a BS sends one to multiple sets of CSI-RS resources to a UE; because an existing CSI measurement mode is measuring each set of resources separately, a measurement result only reflects CSI of ports corresponding to each set of CSI-RS resources, which will cause inaccurate CSI measurement results of all ports of a transmitting array, especially a PMI (precoding matrix indicator) information measurement error in the CSI.